Steroidal composition and cytotoxic activity from fruiting body of Cortinarius xiphidipus.

From the fruiting body of ectomycorrhizal fungi Cortinarius xiphidipus, sterols were identified from the crude extract and the cytotoxic effect of ergosta-4, 6, 8(14), 22-tetraen-3-one (ergone) was evaluated. Ten sterols including ergosta-3,5,7,9(11),22-pentaene, (22E)-ergosta-5,7,9(11),22-tetraen-3b-ol, (3β,22E)-ergosta-5,7,22-trien-3-ol, (22E)-ergosta-7,22-dien-3-ol, neoergosterol, (3β)-ergosta-5,8-dien-3-ol, (3β)-ergosta-7-en-3-ol, stigmasterol, stigmasterol 22,23-dihydro and (22E)-ergosta-4,6,8(14),22-tetraen-3-one were identified from the crude extract. The cytotoxic activity of the sterol fraction containing ergosta-4, 6, 8(14), 22-tetraen-3-one was assessed on four tumour cell lines (Neuro-2a, Saos-2, MCF7 and LNCaP-C42). The cytotoxic activity against the four tumour cell lines tested, being Neuro-2a and Saos-2 the most sensitive, with a half-maximal inhibitory concentration (IC50) of 20.8 ± 2.2 and 27.8 ± 1.0 μg/mL, respectively. This is the first report of this Antarctic fungi collected in the Magallanes and Chilean Antarctica Region. This work represents a potential source for the development of anticancer drugs.